I keep hearing people say Faora's actress trained for the part. I've seen sources that confirm that, but it seemed like a waste of time for her. She wore a bulky suit for 99% of her screen time, and as far as I could tell she was no more fit than Lois. If she was training she probably was, but its not like you could tell in the suit, and its not like she did any partcularly athletic stunts, it was all CG stuff.
Gadot could train for years and still be too small. She's a model, and she's there for eye candy. If she's a good actress that will just be a bonus to the studio. Training or not, she's always going to look like a stiff breeze could knock her senseless. She's just too scrawny to be WW, and no amount of training will fix that.
After seeing some clips of her, I'm not quite sure of her ability to act either, but that could still go either way. Regardless, this casting just sucks, and even if she can act, she could never be a good WW. Its like if they had gone insane and cast Seth Green as Superman. He could train for a decade, he'd still not work. Doesn't mean he's a bad actor, it just means there is no training or trick photography that could make him convincing in the role, and I think Gadot is in the same situation.